Process for reducing agent migration during treatment of knitted cotton fabric

Abstract

Knitted cotton fabrics in tubular form are impregnated to 20 to 35% wet add-on of crosslinking agent by any of several techniques including sprinkling, spraying, printing, or slop padding the solution of crosslinking agent to the outer surfaces of the fabric tube, or transferring the solution of crosslinking agent from impregnated material to the outer surfaces of the fabric tube, followed by a mechanical agitation step wherein the impregnated tubes are mechanically agitated at elevated temperatures under closed conditions, thereby eliminating agent migration toward fabric surfaces during drying of the cotton containing knitted fabrics in chemical treatments for smooth-drying properties and dimensional stabilization.

We claim: 
     
       1. A process for imparting to tubular knitted cotton textiles the enhancing qualities of durable press and dimensional stability by means of a chemical finish that is uniform throughout the fibers of the fabric and results in generally superior properties of the textile and in elimination of shade and color differences between fabric surfaces on subsequent dyeing, the process comprising: a. impregnating the tubular knitted cotton to a wet pick-up of from 20 to 35% with an aqueous solution containing: 1. a methylol amide crosslinking agent,   2. an acid catalyst, and   3. a non-ionic surfactant, and     b. mechanically agitating the impregnated textile for from 10 to 15 minutes at temperatures of from 45° C. to 75° C. while preventing water evaporation from said textile;   c. drying the mechanically agitated moist textile; and   d. curing the dry textile at an elevated temperature.   
     
     
       2. The process of claim 1 wherein the impregnation is effected by spraying the surface of the textile. 
     
     
       3. The process of claim 1 wherein the methylol amide crosslinking agent is selected from the group consisting of dimethylol ethyleneurea and dimethylol dihydroxyethyleneurea, the acid catalyst is selected from the group consisting of magnesium chloride hexahydrate and zinc nitrate hexahydrate, and the surfactant is produced by the etherification of octyl phenol with poly(oxyethylene) glycol. 
     
     
       4. The process of claim 1 wherein the impregnation is effected by transferring the aqueous solution from a knitted cotton fabric padded in said solution to a wet pick-up of 80-100% by passing through squeeze rolls. 
     
     
       5. The process of claim 1 wherein the impregnation is effected by transferring the aqueous solution from polyurethane foam sheeting padded in said solution to a wet pick-up of 80 to 100% by passing through squeeze rolls.